Short-term effect of fresh pomegranate juice on serum cortisol and thyroxine in patients with type 2 diabetes.

BACKGROUND: The effect of pomegranate juice on type 2 diabetic conditions has been determined in various occasions. However, such an effect on cortisol and thyroxine hormones, which are major controllers of energy metabolism, is not yet revealed. OBJECTIVES: In this study, we intended to measure the short-term effect of fresh pomegranate juice on serum cortisol and thyroxine in patients with type 2 diabetes. MATERIALS AND METHODS: This study was a randomized clinical trial in which 89 fasted patients with type 2 diabetes were supplemented with fresh pomegranate juice at a dose of 1.5 mL kg-1. Blood specimens were then collected before and at 1 and 3 hours after juice administration. Serum cortisol and thyroxine were assessed using commercial chemiluminescent-immunoassay kits. RESULTS: Serum cortisol, but not thyroxine, was significantly (P < 0.0001) lower in patients with type 2 diabetes after ingesting fresh pomegranate juice. In addition, no significant correlation (r2 = 0.00003, P = 0.9569) was observed between cortisol response to fresh pomegranate juice and the level of fasting serum glucose in the recruited patients. Moreover, no significant difference (P = 0.9118) in cortisol response to fresh pomegranate juice was found between recruited males and females. CONCLUSIONS: In conclusion, fresh pomegranate juice decreased serum cortisol, 1 hour after juice ingestion, but not serum thyroxine 3 hours after juice ingestion, in patients with type 2 diabetes. In addition, cortisol response to fresh pomegranate juice was found not to be affected by patients’ gender and the level of fasting serum glucose.